Paper pulping apparatus



Sept. 4,, 1945. H. D. MARTINDALE 2,384,326

PAPER PULPING' APPARATUS Filed Aug. 27, 1941 INVENTOR 1] 4Mw/v' HIS ATTWTNEYS atenied Sept. 4, 1945 PAPER PULPING APPARATUS Homer D. Martindale, Middletown, Ohio, assignor to The Black-Clawson Company, Hamilton, Ohio, a corporation of Ohio Application August 27, 1941, Serial No. 408,482

6 Claims.

This invention relates to pulping apparatus for treating fibrous material, and more particularly to apparatus for pulping and screening fibrous material used in the manufacture of paper.

One object of the invention is the provision of a pulping and screening apparatus having a rotatable pulping member which operates a considerable distance above the bottom of a tank, and provided with upper and lower portions both of which are arranged to give a combined pulping action and outward circulation, the pulped material being withdrawn through a screen which is provided within the tank in which the pulping member operates.

Another object of the invention is the provision of apparatus for pulping and screening material used in the manufacture of paper, including a rotatable pulping member arranged a substantial distance above a circular screen, and of greater diameter than the screen, the pulping member having provision whereby a combined pulping and. outward circulation is produced on both its upper and lower sides, the apparatus being such that some of the material thrown outwardly by the pulping member travels upwardly and then back towards the center of the member for further pulping action, while another portion of the material thrown outwardly travels in a downward direction, moves inwardly, and then 1 moves up along the side of the screen so that pulped material fine enough to pass through the screen can be effectively withdrawn.

Other objects and advantages of the invention will be apparent from the following description, the appended claims and the accompanying drawing.

In the drawing:

Fig. 1 is a central vertical section through a pulping apparatus embodying the present invention Fig. 2 is a plain view of the pulping member; and

Fig. 3 is an end view of a portion of the pulping member.

wall of the tank being carried by suitable supports l3. Below the tank is a motor Hi, connected through a suitable gear transmission, contained in a housing IE, to a rotatable shaft l5 which extends up through an opening in the lower wall of the tank. At its upper end the shaft I6 carries a rotatable pulping member IS. The gear transmission is preferably such as to provide'a peripheral speed 'of the member I6 of about 2000 to 6000 feet per minute.

The pulping member l6, as shown, is a plate or disk of steel or other suitable metal with grooves l8 milled in both its upper and lower sides, the depth of the grooves at the periphery of. the plate being preferably about one third of the plate thickness, and sufliciently deep to provide substantial walls presenting sharp edges to act upon the pulp material in the manner herein described. These grooves which may be curved or straight, extend from the periphery to near the center of the disk where the grooves are more shallow in depth. Both the upper and the lower sides of the pulping member are thus provided with alternate vanes or projections and recesses, the outwardly extending sides of the grooves meeting the upper and lower outer surfaces of the disk at substantially right angles to provide sharp edges so that as the disk is rotated rapidly, aneffective pulping action is produced on the material in the tank, and the material is driven outwardly along the upper and lower sides of the disk and thus caused to circulate in the tinuous circulation of the material, with comparatively small power consumption. Some of the material forced outwardly by the rotating pulping member travels upwardly along the cylindrical tank walls and then moves inwardly and downwardly to be again acted on by the pulpin member, the vortex circulation thus produced causing the material to be brought time and again to the pulping member and gradually broken up Or pulped. Some of the material forced outwardly by the pulping member moves downwardly along the tank wall, travels in along the tank bottom and then moves upwardly towards the pulping member again so that it will be again acted on by its lower portion.

Spaced a substantial distance below the pulping member and of substantially smaller diameter than the latter is a screen 2|, preferably of cylindrical form. Within the screen is a discharge chamber 22, provided by the screen itself, the upper imperforate wall 23 which extends across the top of the screen, and the central portion of the bottom wall of the tank. Pulped material flowing through the openings in the screen is withdrawn through an opening 24 in the lower wall of the tank, and flows through a passage 25 which leads to a flow-controlling device shown in the form of a receiver 28 provided with a suitable flow-regulating dam 21 the height of which is adjustable to a desired level a little below the level of the top of the material in the tank to provide a continuous withdrawal of the pulped material at a suitable rate so that the screen openings will not become clogged. These screen openings may be of a diameter of about A inch'or larger, depending on the degree of fineness desired in the finished product.

The tank may have a diameter of several feet. With a tank of about six feet in diameter, the pulping member should have a diameter of from two to three feet. The diameter of the screen is preferably about one-half of the diameter of the pulping member so that the latter extends out radially a considerable distance beyond the screen, the lower side of the disk thus having an effective pulping and propelling action-on the material and inducing an up-flcw along the sides of the screen as the material is circulated in its lower vortex path, so that the finer material which has been sumciently pulped will flow inwardly through the screen openings while materialrequiring further pulping will travel upwardly along the outer side of the screen and return again to the lower side of the pulping member. The up-flow along the outer sides of the screen prevents the screen openings from being clogged. The lower wall of the tank, as shown in Fig: 1, may be provided with an annular depression or well 29 so that metal or other heavy foreign pieces or impurities present in the pulp undergoing treatment may lodge j in the depression as they travel inwardly towards the screen and be withdrawn from time to time under the control of valveV through a suitable clean-out passage 30. The depth of the depression or well 29 increases from some suitable small amount as it extends around the screen in the direction of rotation, reaching a maximum depth at the location of the passage 30 so that the heavy impurities or material collected in the depression will gradually travel around to the clean out pas sage.

' While the form of apparatus herein described constitutes a preferred embodiment of the inyen tion, it is to ix understood that the inventionls not limited to this precise form of apparatus; and that changes may be made therein without departing from the scope,of the invention whi c h is defined in the appended claims.

What is claimed is: 1. Paper pulping apparatus comprising a tank,

, a substantially cylindrical screen in the 2 lower and having sharp pulping edges carried upon the upper and the lower sides of said pulping member and arranged in sequential series around said pulping member on both sides thereof with each said edge arranged in a direction generally radial to the pulping member and effective to act upon the narrow zone of the large bodies of pulp above and below said horizontal pulping member to produce a combined pulping action by successively shearing oil said comparatively thin layers of pulp from the main bodies of the pulp and to cause outward circulation of such sheared material above and below the member under the high rotating speed and thus to cause circulation of the main bodies of pulp into the paths of said sharp edges for said high speed successively sequential shearing actions, the diameter of the pulping member being about twice the diameter of the screen and the diameter of the tank being about three or more times the diameter of the screen.

2. Paper pulping apparatus comprising a tank, a substantially cylindrical screen in the lower portion of the tank providing a discharge chamber therein, a substantially horizontal pulping member rotatably mounted in said tank above the screen in spaced relation with the screen and substantialh' in axial alignment therewith, said member being vertically spaced a considerable distance above said screen and projecting out beyond the screen to provide large bodies of material to be pulped both above and below said member, and said member having sharp pulping edges carried upon the upper and the lower sides of said pulping member and arranged in sequential series around said pulping member on both sides thereof with each said edge arranged in a direction generally radial to the pulping member and effective to act upon the material to be pulped in the comparatively thin zones within the paths of said pr0- jections to produce a combined pulping action by successively shearing off said comparatively thin layers of pulpfrom the main bodies of pulp and to cause outward circulation of such sheared material above and below the member under the high rotating speed and thus to cause circulation of the main bodies of pulp into the paths of said sha p edges for said high speed successively sequential shearing actions, the diameter of the pulping member being about twice the diameter of the screen and the diameter of the tank being about three or more times the diameter of the screen, said tank having an annular well or depression of gradually varying depthln its bottom wall, and having an outlet opening at the location of greatest depth.

3. Paper pulping apparatuscomprising a tank, a substantially cylindrical screen in the lower portionof the tank providing a discharge chamber therein, a pulping disc rotatably mounted in said tank in spaced relation above the screen and substantially in axial alignment therewith, said disc being vertically spaced a considerable distance above said screen and projecting out beyond the screen towards the sides of the tank to provide large bodies of material to be pulped both above and below said disc and having grooves in the upper and lower sides of the disc of gradually increasing depth and extending from near the center of the disc to the disc periphery and provided in the upper and lower sides of the disc, the outwardly extending surfaces of the grooves meeting the surface of the disc to provide a sharp operating edge, and means for rapidly rotating said disc at a peripheral speed of approximately 2000 to 6000 feet per minute, whereby said sharp pulpaseasae ins edges will successively shear ed the comparatively thin zones of pulp within the paths of travel oi said pulping edges in rapid sequential shearing actions to thus cause rapid disintegration of the whole body of pulp through successive rapid disintegration of the small layers within such paths of travel.

4. Paper pulping apparatus of the character described comprising a tank, a rapidly rotatable pulping member in said tank arranged substantially horizontally and a substantial distance above the bottom of the tank and having sharp pulping edges carried upon the upper and the lower sides of said pulping member and arranged in sequential series around said pulping member on both sides thereof with each said edge arranged in a direction generally radial to the pulping member and each presenting a sharp pulping edge effective in action against the comparatively thin adjacent layer of pulp material, and means for rotating said member at high peripheral speed and effective to bring said sharp pulping edges in high speed shearing action against said comparatively thin adjacent layers of the large mass of pulp to cause disintegration or pulping of the pulp material at said sharp edges and to produce an outward circulation of material along both the upper and lower side of said member, and a screen within the tank and a substantial distance below said pulping member and of smaller diameter than said member and positioned in the path of circulation of disintegrated material and through which sumciently disintegrated pulp material is withdrawn.

5. Paper pulping apparatus of the character described comprising a tank, a rapidly rotatable pulping disc in said tank arranged substantially horizontally a substantial distance above the bottom of the tank and having grooves with sharp pulping edges arranged in alternate relationship on opposite sides of said pulping disc, the grooves and sharp shearing edges on each side being arranged in generally radial direction and presenting a series of sharp edges efiective in action against the comparatively thin adjacent layer of pulp material, and means for rotating said pulping disc at high peripheral speed of approximately 2000-6000 feet per minute and effective to bring said sharp edges in high speed shearing action against said comparatively thin layers to shear such thin layers of pulp from the comparatively large main bodies of pulp above and below said pulping disc to cause rapid disintegration or pulp- 111g of the pulp material through such high speed successive actions on the comparatively small quantities of pulp thus successively sheared in high speed sequential actions from the efiective action zones of said sharp edges to produce an outward circulation of material along the upper and the lower side of said pulping disc, and a substantially cylindrical screen substantially coaxial with said pulping disc and spaced a substantial ,distance below, said disc and of smaller diameter than said pulping disc, said screen being positioned in the path of circulation of disintegrated material and having a discharge opening connected to the space inside sai screen.

6. Paper pulping apparatus of the character 7 described comprising a tank, a rapidly rotatable pulping disc in said tank arranged substantially horizontal and a substantial distance above the bottom of the tank to provide large bodies of material to be pulped both above and below the opposite surfaces of said disc, said disc having sharp pulping edges carried upon the upper and the lower sides of said pulping disc and arranged in sequential series around said pulping disc on both sides with each said edge arranged in a direction generally radial to the pulping disc and each said pulping edge presenting a sharp edge eilective in shearing action against the adjacent comparatively thin layer of pulp material, means for rotating said pulp disc at high peripheral speed of approximately 2000 to 6000 feet per minute to bring said sharp edged projections in high speed sequential shearing actions against the comparatively thin layers of pulp in the path of movement of said successive edges to shear successive thin layers of pulp from the main bodies of pulp above and below said disc and to cause said projections thus to eflect a disintegrating or pulping action upon the layers of pulp material successively brought adjacent the disc, and to produce an outward circulation of the sheared oiT material along both the upper and lower sides of said pulping disc, the action of said disc causing circulation of said acted upon material outwardhr against the Wall of the tank and then both upwardly and downwardly back toward the axis of rotation of the disc to thus cause a double circulation in said body of material in the tank to be pulpedwith materialcirculating to be maintained along each rotating face of the disc, and a screen within the tank a substantial distance below said member and of smaller diameter than the member, and positioned in the path of circulation of disi'ntegrated material to have its surface flushed by said HOMER n. 'MAR'I'INDALE. 

